Decompression solenoid, built to fail! - Road Star Warrior Forum : Yamaha Star Warrior Forums

Reply
 
LinkBack Thread Tools
Old 04-22-2012, 12:03 AM   #1 (permalink)
Super Moderator
 
jpwarrior's Avatar
 
Join Date: Nov 2002
Location: Daytona, FL
Posts: 8,496
Default Decompression solenoid, built to fail!

Recently serviced the trans on my bike which required complete removal and re-installation of the motor and most of it's associated components. After getting the motor, and the wiring and fuel systems connected I encountered a fault code 38 on the tach. This is for the decompression solenoid. The fault can be caused by an open circuit and/or an ECU failure.

Assuming the ECU was fine I worked on the possibility that there may be a problem with the solenoid. I removed the solenoid with wire harness and bench tested it. There are 4 wires connected to the solenoid, two are for actuating the solenoid and the other two are thermostat wires built into the solenoid.
The black wires actuate the solenoid. The green wires don't. The solenoid is not serviceable BTW, so if it doesn't work one is to assume that the thing is toast and needs to be replaced. Here's where I found out that there's an issue with the harness which is wrapped in a sheath.

After failing the bench test I tried a continuity test from the black connector to the exposed wires three inches before they entered the back of the solenoid. The first wire failed continuity which meant I had to remove the sheath and expose the wires. About 6 - 8 inches from the solenoid there are two crimp connectors on the black wires which are only electrical taped to protect from the elements. Turns out this is where the wire separated. The elements corroded the exposed wires and one broke when I was removing and replacing it back on the bike. The harness is also protected by a wire loom, but all this protection essentially keeps moisture the harness.

The repair was simple, cut and solder the connection then shrink wrap the area after placing some dielectric grease on the connection. (Bench test the repair to make sure the solenoid actually works.)
Since the sheath was removed I electrical taped the 4 wires all the way up to the connections under the seat and placed the harness back into the loom that contained the cam gear sensor.

The removal can get involved and I'm sure less parts can be exchanged but I pulled the pulley housing off, removed the battery box, and removed the sub fuel tank to re-route the wiring harness properly and with ease. Zip-tie the harness/loom back onto the frame below the transfer case and place the all the wire harnesses back in the clips on the seat tube. Attach all the parts you removed and connect the harness, battery, and ECU.

The part retails for 206.00 -ish but can be purchased as low as 133.00-ish if you shop around. I know of a friend who had to replace this because the dealer didn't check the harness. This can save you a chunk money in labor costs as well as the part cost if you bring this to a dealer for service.

Wiring diagram courtesy of Alanh:

Last edited by jpwarrior; 04-22-2012 at 06:58 PM.
jpwarrior is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 04-22-2012, 01:00 AM   #2 (permalink)
Senior Member
 
Join Date: Jan 2010
Location: WNY
Posts: 3,448
Default

This is awesome to know and should ABSOLUTELY go in the "popular mods and repair knowledge base".

Great write up, review and technical description. Excellent info to have for all DIY repair/service Warrior owners.

Thank you!
__________________
"If you ever see a Speed Triple rider on the road, who's not doing a wheelie, then he is deliberately not doing a wheelie. And you probably shouldn't be doing one either" Loz Blain


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
07midnight57 is offline   Reply With Quote
Old 04-22-2012, 02:31 AM   #3 (permalink)
Super Moderator
 
arizonawarrior's Avatar
 
Join Date: Jan 2005
Location: Reno Nevada and Rogue River Oregon
Posts: 27,351
Blog Entries: 4
Default

Another notch on yer pistol grip buddy, nice trouble shooting and great write-up. Built to fail is an accurate description, and now that we know we can beat the system. Thanks!
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
arizonawarrior is offline   Reply With Quote
 
Old 04-22-2012, 05:02 AM   #4 (permalink)
Senior Member
 
Caledonian Warrior's Avatar
 
Join Date: Jan 2011
Location: Scotland, UK.
Posts: 1,984
Default

Excellent write-up JP.
That's good to know, thanks.

Gav.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


TO SEE OLD PHOTOBUCKET IMAGES WITH FIREFOX..
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


TO SEE OLD PHOTOBUCKET IMAGES WITH GOOGLE CHROME..
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.







Caledonian Warrior is offline   Reply With Quote
Old 04-22-2012, 06:00 AM   #5 (permalink)
Senior Member
 
tomba's Avatar
 
Join Date: May 2008
Location: whitstable kent uk
Posts: 5,858
Send a message via Skype™ to tomba
Default

Quote:
Originally Posted by Caledonian Warrior View Post
Excellent write-up JP.
That's good to know, thanks.

Gav.
D I T T O - excellent ...good read to...thank you

it's going into pop mods
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


WARRIOR - OIL CHECK VIDEO
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
tomba is offline   Reply With Quote
Old 04-22-2012, 09:43 AM   #6 (permalink)
Senior Member
 
jabo's Avatar
 
Join Date: Feb 2004
Location: Southeastern Kentucky
Posts: 7,914
Default

Great job.
jabo is offline   Reply With Quote
Old 04-22-2012, 10:21 AM   #7 (permalink)
Super Moderator
 
jpwarrior's Avatar
 
Join Date: Nov 2002
Location: Daytona, FL
Posts: 8,496
Default

I was so pissed (not drunk for you overseas mates) when I found this, that I had to post it up. I have seen this before on this bike and also on my R1's harness. It's been a while since I had to put my thinking cap on (usually a drinking cap) to diagnose a failed part which was functioning just prior to doing the some sort of service work. I have no idea why this would not have a solid connection to the solenoid from the under-seat connection other than to build in some degree of failure for future parts and service revenue.

I saved myself a chunk of change, that alone was worth the effort. I hope this failure doesn't come across your path but if it does, you'll have some knowledge about a possible cause for the failure and how to repair it.
jpwarrior is offline   Reply With Quote
Old 04-22-2012, 11:44 AM   #8 (permalink)
Senior Member
 
alanh's Avatar
 
Join Date: May 2004
Location: The Mitten State
Posts: 8,254
Thumbs up

Excellent trouble shooting and neat technical write-up ... thank you

Why don't you retitle this thread and place it as a sticky in the : How To's and General Maintenance Tips
__________________
***1187***

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
- Starting System
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
&
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
&
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
alanh is offline   Reply With Quote
Old 04-22-2012, 12:14 PM   #9 (permalink)
Senior Member
 
1256day's Avatar
 
Join Date: Jul 2010
Location: Chino Hills
Posts: 4,741
Default

JP, Great write up!

1 question, Do you think the wires in question might have become brittle due to being subjected to high heat cycles and vibration? Which could cause the insulation to crack and expose the wire to moisture, corrosion, then failure.

The reason I ask, is I've noticed over the years and miles on various bikes, the insulation on wires subjected to high heat cycles and vibration become very brittle and then componet failure.

For example Pick up coils on Yami XS1100's and Hall Effect Sensors on BMW's. (same thing)

I finally found some High Tempature Teflon Insulated wires and was able to fix these issues and like you, save money.

In case of the BMW, well over a $1000.

FYI, This Wire is very expensive to buy because you have to buy it in 200ft rolls. I found Ford Electronics in Fullerton CA sells it by the foot, in any color combination and wire dia.

I have often wondered if the CPS failure was due to this issue?

Again nice write up.

G
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Last edited by 1256day; 04-22-2012 at 12:15 PM. Reason: add
1256day is offline   Reply With Quote
Old 04-22-2012, 12:51 PM   #10 (permalink)
Super Moderator
 
jpwarrior's Avatar
 
Join Date: Nov 2002
Location: Daytona, FL
Posts: 8,496
Default

Thanks.

To answer your question, no. In this case the wires were butt spliced from the factory as a continuous wire with a crimp connector and were susceptible to moisture because the splice was never insulated properly. I suppose if I never moved the wire I might have gotten another year or two out of it. Removal from the wire loom wasn't necessary and in retrospect I don't know why I did this as I could have kept the whole bundle together. I suppose my thinking was that the solenoid connection may have become brittle, so it was to prevent what I directly caused where I assumed it wouldn't happen. I foresee it failing again because the repair IMO, isn't as good as a continuous insulated wire, although it's a far sight more thorough than what was done originally.

Quote:
Originally Posted by 1256day View Post
JP, Great write up!

1 question, Do you think the wires in question might have become brittle due to being subjected to high heat cycles and vibration? Which could cause the insulation to crack and expose the wire to moisture, corrosion, then failure.

The reason I ask, is I've noticed over the years and miles on various bikes, the insulation on wires subjected to high heat cycles and vibration become very brittle and then componet failure.

For example Pick up coils on Yami XS1100's and Hall Effect Sensors on BMW's. (same thing)

I finally found some High Tempature Teflon Insulated wires and was able to fix these issues and like you, save money.

In case of the BMW, well over a $1000.

FYI, This Wire is very expensive to buy because you have to buy it in 200ft rolls. I found Ford Electronics in Fullerton CA sells it by the foot, in any color combination and wire dia.

I have often wondered if the CPS failure was due to this issue?

Again nice write up.

G
jpwarrior is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply

  Road Star Warrior Forum : Yamaha Star Warrior Forums > Library Section > How To's and General Maintenance Tips

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 07:43 PM.


Powered by vBulletin® Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.6.0
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
RSWarrior.com is an independent Yamaha enthusiast website. Content on RSWarrior.com is generated by its users and RSWarrior.com is not in any way affiliated with Yamaha Motor Corporation, U.S.A.